1. Field of the Invention
The present invention relates generally to communication between circuits that use galvanic isolation, and more specifically to communication across an isolation barrier in switch mode power converters.
2. Discussion of the Related Art
Electrical devices in many contexts include a communication system that sends information between a transmitter and a receiver that are galvanically isolated and referenced to different ground potentials. Examples include power converters, medical equipment, marine equipment, and the like.
One such communication system uses magnetically coupled wires to send information between a transmitter and a receiver. Otherwise also known as an inductive coupling, a varying current flowing through a transmitting conductor induces a voltage across the ends of a receiving conductor. The coupling between the conductors can be strengthened in various ways. For example, conductive wires may be formed into coils with or without a magnetic core. Examples of inductive couplings include a transformer and a coupled inductor.
Despite the magnetically coupling of such conductors, the conductors can remain electrically isolated from each other so that a voltage difference can be applied without significant electrical conduction therebetween. However, so long as the magnetic coupling between the conductors is sufficiently strong, information can be conveyed across this electrical isolation.